Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [parallel]

More than one of a thing, performing the same task simultaneously

This is a broad tag. Applicable to current flow components (resistors, capacitors, inductors, transistors, diodes), logic components (CPUs, FPGAs), or software tasks (multiple threads or processes). It can mean completely different things in each domain.

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Why exactly can't a single resistor be used for many parallel LEDs?

Why can't you use a single resistor for a number of LEDs in parallel instead of one each?
Dataflashsabot
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What would happen if I connect two different DC voltage sources in parallel?

I have a computer power supply that I'm hacking together as a bench supply. For this particular model to power on, I need a minimum load across both +5V and +12V. "Easy," I thought, "I'll just connect both +5 and +12 to my power resistor!" And it…
rascher
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Is paralleling diodes a bad idea?

I'm trying to repair an 800W power supply (see my previous question on this.) One thing that gets me is that the design has two schottky diode packages (in TO-220) in parallel. I was always told this was A Bad Idea, but since they are thermally…
Thomas O
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Parallel MOSFETs

When I went to school we had some basic circuit design and stuff like that. I learned that this was a bad idea: simulate this circuit – Schematic created using CircuitLab Since the current will almost certainly not flow equally over these three…
BufferOverflow
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Two resistors in series

I know the summation equation for two or more resistors in parallel or series, and I know two parallel resistors will give more power. But sometimes I saw some circuits that used two resistors in series, and I am wondering why that method was used…
M.A.K
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Will a 0402 0.01 µF ceramic capacitor next to a 0402 0.1 µF ceramic capacitor have any power decoupling benefits?

I always understood that the point of using smaller capacitors in parallel was to provide low impedance at higher frequencies than the bigger capacitors, because the higher capacitance capacitors 'usually' had larger packages, so the parasitic…
apalopohapa
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Transistors in parallel

I want to use several transistors in parallel to control current through a load. This is to distribute the current through the load across the transistors so that individual transistors with a rated collector current less than that going through the…
Jodes
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How many MOSFETs can we safely parallel for very high currents? I had problems with a motor application at 48 V, 1600 A

I tried with some configurations in which 16+16 MOSFETs of 240 A each (really they are case limited to 80-90 A because of source terminal, but I doubled this termminal with a very thick copper wire for each of them) were configured in a very…
addysoftware
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Why is the serial connection faster than the parallel connection?

As a software developer the concept of parallel processing usually meant faster processing because it meant things don't have to wait for the other processes to finish if they don't need to. So how come the serial connection is looked at (arguably)…
M. A. Kishawy
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How do I calculate the current in parallel branches?

I've been playing around with an Arduino for a while now, and while I know just enough about simple circuits to get little projects up and running, I still don't know enough to figure out what's going on in all but the simplest of circuits. I've…
littlecharva
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What's wrong with parallel conductors?

Regarding AC systems (like for homes and such), a circular path is called a parallel conductor. It's illegal (according to the NEC section 310) except under certain circumstances. But I have noticed that with DC circuits, circular conductors are…
Ben Welborn
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Is it good practice to parallel relay contacts for increased current capacity?

Say I have a DPDT relay, like T92S7D12-24. The contacts of this relay are rated for 30A, but there are two sets of contacts. Can I parallel the contacts to get an effective 60A relay? Further, could I parallel two (or more) relays and get even more…
Stephen Collings
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Why does current not increase when batteries are connected in parallel?

I built a simple circuit consisting of two battery holders each including x2 1.5 V batteries, a slide switch, a LED and a 100 ohm resistor. The current I measured with a multimeter when the two battery holders were connected in series (and the…
korppu73
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In FPGAs, is it safe to execute non-blocking assignments like `b <= a; a <= 0;` in the same clock cycle?

I have a piece of code in Verilog which needs to assign the value of shift register to an output register when the shifting has finished, and I want to reset the value of the shift register in the same clock cycle. Like the following: [shift…
Martel
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Why do we use two parallel capacitors in a voltage regulator circuit?

C1 and C2 are parallel capacitors and their total capacitance is 1000.1 uF. I think C1 is large enough and I can remove C2 from the circuit. The result will be an open circuit. Let's assume that I can buy one capacitor that has the value of 1000.1…
Michael George
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